The invention relates to data input devices. More particularly, the invention relates to distal chording keyboards.
Data input devices generally represent a main component of a computer system. Through them a user can provide alphanumeric and special function input to provide user control and data to be stored and/or manipulated on the computer system. The present data input device standard is a combination of the QWERTY keyboard together with a mouse for cursor control. The QWERTY keyboard is named for its key configuration, with xe2x80x9cQxe2x80x9d, xe2x80x9cWxe2x80x9d, xe2x80x9cExe2x80x9d, xe2x80x9cRxe2x80x9d, xe2x80x9cTxe2x80x9d, and xe2x80x9cYxe2x80x9d being the letters from left to right on the top row of letter keys. The QWERTY keyboard has one key for each letter in the alphabet, the keys are typically labeled with the capital letter of the letter the key produces when depressed. The QWERTY keyboard also has keys for each number 0 through 9, as well as punctuation and control function keys. Most alphanumeric input is accomplished by a single key press on the keyboard. Some other input is accomplished by a combination key press of a control function key and an alphanumeric key. Cursor control may be provided by, for example, a mouse, trackball, cursor post, touchpad, etc.
One drawback to the QWERTY keyboard is that its key configuration is based in part on a negative application of frequency of use of alphanumeric characters in American English. The QWERTY keyboard was designed to be used in mechanical typewriters, where individual hammers would produce a character. Frequently used characters were spaced apart to prevent a proficient typist from jamming the hammers by typing too fast. However, this necessarily means that characters are not spaced on the keyboard for ease of use of a user.
Another drawback to the QWERTY keyboard is that the planar key layout has the potential to cause physical discomfort or even injury from extended use. This problem of ergonomics has been the motivation behind many efforts to create keyboards that better match the natural position of the hands. For example, QWERTY keyboards are produced that are split down the middle with the left-hands portion sloping down to the left, and the right-hand portion sloping down to the right. Other keyboards have been designed that dispose the keys on the distal side of the device (on the side of the keyboard facing away from the user) such that the fingers curve around the device to where the keys are located. However, these distal keyboards generally do not provide all the functionality possible with a QWERTY keyboard and cursor control combination that is standard to data input.